In a method and system for effecting bi-directional IR data communication between an object transceiver and a reader, the object transceiver transmits successive data packets to the reader, and upon termination of a transmission of each data packet, opens a time window for receiving a transmission from the reader. The object transceiver is typically one of a plurality of object transceivers each worn by a person to whom a short message is to be transmitted and each having a respective unique ID and being able to effect autonomous transmission to the reader. In such case, each object transceiver transmits for a negligible fraction of its duty cycle thereby reducing a likelihood that two or more object transceivers will try to transmit simultaneously. Alternatively, the same objective can be realized by controlling each object transceiver to have a randomly variable duty cycle.
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11. A reader for sending a message using IR data communication to a portable transceiver, said reader comprising:
a receiver for receiving a transmission of a data packet from the portable transceiver, and a transmitter for sending the message to the portable transceiver during a time window opened thereby; wherein the transmitter is responsive to the received data packet from the portable transceiver for sending said message and is thus incapable of initiating autonomous communication with the portable transceiver.
1. A method for effecting bi-directional IR data communication between an portable transceiver and a reader, the method comprising the following steps carried out by the portable transceiver:
(a) initiating asynchronous transmissions of successive data packets to the reader at a rate that is dependent on whether the portable transceiver is stationary or moving, (b) upon termination of a transmission of each of said data packets, opening a time window for receiving a transmission from the reader and enabling reception of a message therein, and (c) upon termination of said time window, disabling reception of data.
7. A portable transceiver adapted for bi-directional IR data communication with a reader, the portable transceiver comprising:
a motion sensor for producing a motion detect signal upon movement of the portable transceiver, a transmitter coupled to the motion sensor for transmitting successive data packets to the reader at a rate that is dependent on whether the portable transceiver is stationary or moving; a timer responsive to termination of a transmission of each of said data packets, for opening a time window for receiving a transmission from the reader, and a receiver for receiving messages only during said time window.
14. A system comprising:
a plurality of portable transceivers adapted for bi-directional IR data communication with a reader; each portable transceiver comprising: a motion sensor for producing a motion detect signal upon movement of the portable transceiver, a transmitter coupled to the motion sensor for transmitting successive data packets to the reader at a rate that is dependent on whether the portable transceiver is stationary or moving; each reader comprising: a receiver for receiving a transmission of a data packet from the portable transceiver, and a transmitter for sending the message to the portable transceiver during a time window opened thereby; wherein each portable transceiver further comprises: a timer responsive to termination of a transmission of each of said data packets, for opening a time window for receiving a transmission from the reader, and a receiver for receiving messages only during said time window; the transmitter in each reader is responsive to the received data packet from the portable transceiver for sending said message and is thus incapable of initiating autonomous communication with the portable transceiver; and a server is connected to the readers and is adapted to receive and monitor the transmissions of the portable transceivers.
2. The method according to
the portable transceiver is one of a plurality of portable transceivers each worn by a person to whom a short message is to be transmitted and each having a respective unique ID and being able to effect autonomous transmission to the reader, and in step (a) each portable transceiver transmits for a negligible fraction of its duty cycle thereby reducing a likelihood that two or more portable transceivers will try to transmit simultaneously.
3. The method according to
the portable transceiver is one of a plurality of portable transceivers each worn by a person to whom a short message is to be transmitted and each having a respective unique ID and being able to effect autonomous transmission to the reader, and in step (a) each portable transceiver has a randomly variable duty cycle thereby reducing a likelihood that two or more portable transceivers will try to transmit simultaneously.
4. A method for use with a data communications network comprising a server connected to a plurality of readers in order to send a message using IR data communication to a portable transceiver operating according to
(a) awaiting receipt of a transmission from said portable transceiver of a data packet, and (b) sending the message to the portable transceiver from the respective reader in communication with the portable transceiver during a time window opened thereby so as to be dependent on the transmission from the portable transceiver for allowing communication therewith.
5. The method according to
locating the respective reader in communication with the portable transceiver, and sending the message from the server to the respective reader for onward transmission to the portable transceiver.
6. The method according to
8. The portable transceiver according to
9. The portable transceiver according to
10. The portable transceiver according to
12. The reader according to
a signal strength indicator and detector for measuring a received signal strength, a noise subtract unit coupled to the signal strength indicator and detector, a noise integrator coupled to an output of the signal strength indicator and detector for producing a noise signal representative of average noise, a summing amplifier having a first input coupled to an output of the noise integrator and having a second input coupled to a noise threshold for producing at an output thereof an output signal corresponding to the sum of the average noise and the noise threshold, a comparator having an inverting input coupled to the output of the summing amplifier and a noninverting input coupled to the signal strength indicator and detector for producing an output signal only if the received signal strength exceeds the sum of the average noise and the noise threshold.
13. The reader according to
a peak detector coupled to the signal strength indicator and detector for measuring a peak value of the signal strength, a summing amplifier having a first, summing input coupled to the output of the peak detector and having a second, subtracting input connected to a noise threshold for producing at an output of the summing amplifier a signal corresponding to the difference between the peak value of the RSSI signal and the threshold, a comparator having an inverting input coupled to the output of the summing amplifier and having a non-inverting input coupled to the amplifier and detector for producing at an output thereof an output signal only if the signal strength of the received signal exceeds the difference between the peak value of the received signal strength and the threshold, and a deglitcher coupled to the output of the comparator for suppressing any pulse whose time duration is less than a predetermined time period and thus constitutes spurious glitches rather than actual data.
15. In the system according to
(a) locating a respective one of said readers in communication with the portable transceiver, and (b) redirecting the message to the respective reader for onward transmission to the portable transceiver during a time window opened thereby.
16. In the system according to
(a) the portable transceiver initiating transmissions of successive data packets to the reader at a rate that is dependent on whether the portable transceiver is stationary or moving, said data packets including an acknowledge signal where appropriate for acknowledging receipt of a message from the reader during a preceding communication cycle, (b) upon termination of a transmission of each of said data packets, the portable transceiver opening a time window for receiving a message from the reader and enabling reception of data therein, (c) upon termination of said time window, the portable transceiver disabling reception of data so as to conserve battery power, decoding said message and, if necessary, executing any instructions embedded in said message, (d) upon receipt of a data packet from the portable transceiver by one of the readers, the reader decoding the data packet and conveying to the server, (e) if a message is to be conveyed to the portable transceiver, the reader transmitting said message within said time window so as to be received by the portable transceiver, (f) reverting to "receive" mode upon termination of said time window for receiving subsequent data packets from the portable transceiver.
17. The method according to
adapting each portable transceiver to transmit for a negligible fraction of its duty cycle thereby reducing a likelihood that two or more portable transceivers will try to transmit simultaneously.
18. The method according to
adapting each portable transceiver to transmit for a randomly variable duty cycle thereby reducing a likelihood that two or more portable transceivers will try to transmit simultaneously.
19. The method according to
adapting each portable transceiver to initiate said transmission at a randomly varying time within a duty cycle of the transmitter thereby reducing a likelihood that two or more portable transceivers will try to transmit simultaneously.
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This invention relates to a method and system for sending messages using low consumption portable tags that may be affixed to moving personnel or objects.
There are many situations in which it is required to alert or send messages to moving personnel. For example, in an office or hospital environment wherein members of staff move from one room to another, it is frequently necessary to send short messages to a staff member advising him or her, for example, of an incoming telephone message or an imminent appointment. One way in which this can be done is for each staff member to wear a portable tag which contains a memory for storing a unique identity which may be read by a respective interrogation device or reader located somewhere in each room. The tag may be provided with a buzzer for alerting the wearer of an incoming message shown on a display device in the tag. The portable tag transmits its ID at regular intervals to the reader so as to allow determination thereby of which portable tags are located in its vicinity. Whenever the person bearing the tag moves into a new room, his or her identity is automatically determined for onward transmission to a central tracking computer, which keeps a record of each person's ID and his or her corresponding location.
The requirement that each portable tag must constantly transmit its ID to the interrogation device is undesirable because, by their very nature, the portable tags are miniature devices that are energized by a small internal power source such as a battery. The more data which is transmitted by each portable tag, the greater is the energy consumption and the more often the battery must be replaced.
Yet a further consideration must be borne in mind when data is transmitted using optical transceivers. For example, infrared (IR) transceivers are particularly suited for the kind of task in question and require an optically transparent path unencumbered by obstacles for effective data transmission. On the other hand, if even inadvertently optical transparency is maintained between one room and an adjacent room, then there exists the risk that a portable tag located in one room might transmit its ID to the interrogation device associated with a different, adjacent room. Such optical transparency might, for example, be the result of a dividing door between the two rooms being ajar; or owing to a window between the two rooms permitting infrared transmission therethrough.
Our co-pending Israeli Patent Application No. 126799 filed on Oct. 29, 1998 is directed to such a system which permits more than one portable tag to communicate with the interrogation device simultaneously. This desideratum clashes with the requirement to avoid collisions which, with IR transceivers is particularly onerous on account of the fact that it is difficult to detect collisions owing to the half-duplex communications protocol inherent in IR transmission. Such a requirement is met by assigning time slots for each of the IR transceivers and using polling techniques, thus allowing the interrogation device to address a portable tag at will by including the portable tag's ID in the data stream transmitted thereby.
Such a system is thus highly versatile but at the cost of requiring a sophisticated data communications protocol. Furthermore, since a portable tag can be addressed at will, it must always be ready to receive data transmitted thereto by the interrogator. This requirement can be met by making the portable tag constantly active. However, bearing in mind that the portable tag is battery powered, this imposes an unacceptable burden on the battery. Alternatively, battery power may be conserved if the portable tag is normally dormant. However, in this case the portable tag must be "awakened" by the interrogator before data can be received by the portable tag. This places yet a further overhead on the circuitry in the portable tag's receiver, thereby increasing its cost.
When short messages are required to be transmitted to the tag in order to alert the bearer thereof to take certain action, for example, the quantity of data that needs to be transmitted to the portable tag is minimal. It is then possible to dispense with the requirement for independent free addressing of the portable tag. In such cases, the overhead associated with the sophisticated data communications in the system described in Israeli Patent Application No. 126799 may not be warranted.
It is thus an object of the present invention to provide a method for keeping track of objects in which the drawbacks described above are significantly reduced or eliminated.
It is a particular object of the present invention to provide an improved communications protocol suitable for use with IR transceivers allowing near simultaneous two-way communication between an interrogation device and a plurality of IR transceivers.
In accordance with a broad aspect of the invention there is provided a method for effecting bi-directional IR data communication between an object transceiver and a reader, the method comprising the following steps carried out by the object transceiver:
(One) transmitting successive data packets to the reader,
(Two) upon termination of a transmission of each of said data packets, opening a time window for receiving a transmission from the reader.
In accordance with a further aspect of the invention there is provided an object transceiver adapted for bi-directional IR data communication with a reader, the object transceiver comprising:
a transmitter for transmitting successive data packets to the reader, and
a timer responsive to termination of a transmission of each of said data packets, for opening a time window for receiving a transmission from the reader.
The invention also encompasses a reader for sending a message using IR data communication to a portable object transceiver, said reader comprising:
a receiver for receiving a transmission of a data packet from the portable object transceiver, and
a transmitter for sending the message to the portable object transceiver during a narrow time window opened thereby.
Furthermore, the invention encompasses a system comprising a server connected to a plurality of readers for sending a message using IR data communication to a portable object transceiver, wherein the server is adapted to:
(One) locate a respective one of said readers in communication with the portable object transceiver, and
(Two) send the message from the server to the respective reader for onward transmission to the portable object transceiver during a narrow time window opened thereby.
The object transceiver may be a portable battery-powered badge worn by movable personnel to whom short messages are to be communicated. In order to reduce the risk of data collision between different badges, each badge transmits for only 2 ms, successive data being transmitted after 60 seconds if the badge is stationary. In such case, the likelihood of two badges attempting to transmit during the identical 2 ms period is clearly negligible. When the badges move, the time interval between successive transmissions is randomly varied between 3 and 5 seconds. Thus, here too, the risk of two or more badges attempting to transmit within the same time slot may be sufficiently reduced. Obviously, conventional data collision techniques requiring re-allocation of time slots and re-transmission of data may be employed in the event that, notwithstanding efforts to the contrary, two different badge IDs are transmitted simultaneously.
In order to understand the invention and to see how the same may be carried out in practice, a preferred example of the communications protocol will now be described with reference to a portable identity badge, by way of non-limiting example only, with reference to the accompanying drawings, in which:
Owing to the very small time slot during which a stationary badge transmits as a proportion of the overall cycle between successive transmissions, the likelihood of two stationary badges attempting to transmit during the identical 2 ms period is negligible. When the badges move, the time interval between successive transmissions is randomly varied between 3 and 5 seconds. Thus, here too, the risk of two or more badges attempting to transmit within the same time slot may be sufficiently reduced. Obviously, conventional data collision techniques requiring re-transmission of data may be employed in the event that, notwithstanding efforts to the contrary, two different badges are transmitted simultaneously.
Coupled to the micro-controller 35 is a buzzer 36 and a display 37 as well as an array of manual switches S1 and S2 allowing pre-programmed functions to be manually selected in accordance with the instruction set stored in the microcontroller 35. The buzzer 36 and the display 37, in addition to the manual switches S1 and S2, allow customization of the badge for specific applications. Thus, for example, the badge can serve as a paging device for displaying a short message upon receiving a remote communication and sounding the buzzer so as to alert the owner of an awaiting message. A motion sensor 38 is coupled to the micro-controller 35 for feeding thereto a motion signal when the badge is moved. This signal causes the badge to transmit its data at a higher rate and prolongs battery life, since only relatively sparse transmission is required when the badge is stationary. The badge circuitry is powered by a 3 volt lithium battery 39 connected to the micro-controller 35 and the IR transmitter 42 via a power supply controller 40.
To this end there is coupled a noise subtract unit 50 an output of which is fed to a capacitor 51 operating as a noise integrator whose output is fed to a first input of a summing amplifier 52. A second input of the summing amplifier 52 is connected to a variable threshold generator 53 whose threshold may be set by a variable resistor 54 external to the IR receiver 32. The output of the summing amplifier 52, corresponding to the sum of the average noise and the noise threshold, is fed to the inverting input of a comparator 55 whose non-inverting input is fed to the RSSI signal produced by the amplifier and detector 49. The output of the comparator 55 is fed to a deglitcher 56 which suppresses any pulse whose time duration is less than 25 μs and thus constitutes spurious glitches rather than actual signal data. Thus, when a signal is detected at the output of the deglitcher 56, corresponding to an actual received signal, the corresponding data associated therewith is extracted and detected.
To this e, the RSSI signal is fed to a peak detector 60 which measures its peak value and feeds it to a first, summing input of a summing amplifier 61 having a second, subtracting input connected to a variable threshold generator 62 whose threshold may be set by a variable resistor 63 external to the IR receiver 32. The output of the summing amplifier 61, corresponding to the difference between the peak value of the RSSI signal and the threshold, is fed to the inverting input of a comparator 64 whose non-inverting input is fed to the RSSI signal produced by the amplifier and detector 49. The output of the comparator 64 is fed to a deglitcher 65 which suppresses any pulse whose time duration is less than 25 μs and thus constitutes spurious glitches rather than actual data. The waveforms associated with the decoded data and the RSSI signals are shown in
A fixed delay after transmitting data to the reader, the IR receiver 32 within the badge is activated for a time window of 5 ms duration for receiving data transmitted to the badge from a reader. In the absence of any such data being received, the badge returns to standby mode. Otherwise, the received data is displayed and the buzzer is activated to alert the bearer of the badge to the arrival of a message. Thereafter, the badge returns to standby mode.
Thus the invention provides a very simple communications protocol for use by a portable IR badge allowing a badge to receive data for only a short time following transmission of data by the badge. Owing to the sparse transmission rate when the badge is stationary and the fact that a badge can only be addressed by a reader following transmission by the badge to the reader, the badge can be active continually. This obviates the need for "wake up" circuitry and simplifies the IR receiver in the badge.
It will further be appreciated that whilst the communications protocol has been described with particular reference to its implementation in a portable ID badge for tracking movement of a person and allowing short messages to be transmitted thereto, it may equally well be employed in other applications and is clearly not restricted to such a system.
In the method claims that follow, alphabetic characters used to designate claim steps are provided for convenience only and do not imply any particular order of performing the steps.
Radomsky, Israel, Abrams, Israel, Bruslavsky, Yossef
Patent | Priority | Assignee | Title |
10050705, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light interior room and building communication system |
10051714, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light control assembly and system |
10205530, | May 06 2013 | Federal Law Enforcement Development Services, Inc. | Network security and variable pulse wave form with continuous communication |
10250329, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light fixture |
10374706, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light broad band over power line communication system |
10411746, | Apr 01 2009 | Federal Law Enforcement Development Services, Inc. | Visible light communication transceiver glasses |
10448472, | Aug 11 2015 | Federal Law Enforcement Development Services, Inc. | Function disabler device and system |
10595696, | May 01 2018 | SHARKNINJA OPERATING LLC | Docking station for robotic cleaner |
10763909, | Apr 01 2009 | Federal Law Enforcement Development Services, Inc. | Visible light communication transceiver glasses |
10812186, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light fixture |
10820391, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light control assembly and system |
10911144, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light broad band over power line communication system |
10932337, | Aug 11 2015 | Federal Law Enforcement Development Services, Inc. | Function disabler device and system |
10952578, | Jul 20 2018 | SHARKNINJA OPERATING LLC | Robotic cleaner debris removal docking station |
11018774, | May 06 2013 | Federal Law Enforcement Development Services, Inc. | Network security and variable pulse wave form with continuous communication |
11191403, | Jul 20 2018 | SHARKNINJA OPERATING LLC | Robotic cleaner debris removal docking station |
11200794, | Aug 11 2015 | Federal Law Enforcement Development Services, Inc. | Function disabler device and system |
11201672, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light fixture |
11234572, | May 01 2018 | SHARKNINJA OPERATING LLC | Docking station for robotic cleaner |
11265082, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light control assembly and system |
11424781, | Apr 01 2009 | Federal Law Enforcement Development Services, Inc. | Visible light communication transceiver glasses |
11497363, | Jul 20 2018 | SHARKNINJA OPERATING LLC | Robotic cleaner debris removal docking station |
11552712, | May 06 2013 | Federal Law Enforcement Development Services, Inc. | Network security and variable pulse wave form with continuous communication |
11583158, | Aug 01 2018 | SHARKNINJA OPERATING LLC | Robotic vacuum cleaner |
11651680, | Aug 11 2015 | Federal Law Enforcement Development Services, Inc. | Function disabler device and system |
11664895, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light control assembly and system |
11664897, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light fixture |
11783345, | Jan 15 2014 | Federal Law Enforcement Development Services, Inc. | Cyber life electronic networking and commerce operating exchange |
11824586, | May 06 2013 | Federal Law Enforcement Development Services, Inc. | Network security and variable pulse wave form with continuous communication |
6837440, | Oct 03 2002 | Winbond Electronics Corp | Contactless and intelligence-wise code identification chip system |
7111255, | Jun 25 2001 | LinkedIn Corporation | Time-based evaluation of data verification results |
7221750, | Jan 20 2006 | Cisco Technology, Inc. | Intelligent association of nodes with pan coordinator |
7386276, | Aug 27 2002 | CASCADES VENTURES, INC | Wireless information retrieval and content dissemination system and method |
7515917, | Jul 12 2005 | Qwest Communications International Inc | Efficiently determining the location of a mobile communications device system and methods |
7899469, | Jul 12 2005 | Qwest Communications International Inc | User defined location based notification for a mobile communications device systems and methods |
8188878, | Nov 15 2000 | Federal Law Enforcement Development Services, Inc.; FEDERAL LAW ENFORCEMENT DEVELOPMENT SERVICES, INC | LED light communication system |
8188879, | May 24 2007 | Federal Law Enforcement Development Services, Inc.; FEDERAL LAW ENFORCEMENT DEVELOPMENT SERVICES, INC | LED light global positioning and routing communication system |
8331790, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light interior room and building communication system |
8355363, | Jan 20 2006 | Cisco Technology, Inc. | Intelligent association of nodes with PAN coordinator |
8543505, | Jan 14 2011 | Federal Law Enforcement Development Services, Inc.; FEDERAL LAW ENFORCEMENT DEVELOPMENT SERVICES, INC | Method of providing lumens and tracking of lumen consumption |
8571411, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light broad band over power line communication system |
8593299, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light global positioning and routing communication system |
8687965, | May 24 2007 | FEDERAL LAW ENFORCEMENT DEVELOPMENT SERVICES, INC ; Federal Law Enforcement Development Services, Inc. | LED light dongle communication system |
8725173, | Jul 12 2005 | Qwest Communications International Inc. | User defined location based notification for a mobile communications device systems and methods |
8744267, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | Building illumination apparatus with integrated communications, security and energy management |
8750718, | Feb 19 2009 | Samsung Electronics Co., Ltd; The Chancellor, Masters and Scholars of the University of Oxford | Apparatus for controlling lighting equipment for lighting communication |
8751390, | Jan 14 2011 | Federal Law Enforcement Development Services, Inc. | Method of providing lumens and tracking of lumen consumption |
8814084, | May 25 2010 | NEW CREATE LTD | Controllable buoyant system and method |
8886045, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light broad band over power line communication system |
8890773, | Apr 01 2009 | Federal Law Enforcement Development Services, Inc. | Visible light transceiver glasses |
8902076, | Nov 15 2000 | Federal Law Enforcement Development Services, Inc. | LED light communication system |
9100124, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED Light Fixture |
9246594, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light dongle communication system |
9252883, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light global positioning and routing communication system |
9258864, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light control and management system |
9265112, | Mar 13 2013 | Federal Law Enforcement Development Services, Inc. | LED light control and management system |
9294198, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | Pulsed light communication key |
9301090, | Jun 12 2012 | Ricoh Company, Ltd. | Light device, communication unit and positional information management system |
9363018, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light interior room and building communication system |
9413457, | Nov 15 2000 | Federal Law Enforcement Development Services, Inc. | LED light communication system |
9413459, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light dongle communication system |
9414458, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light control assembly and system |
9420453, | Jul 12 2005 | Qwest Communications International Inc. | Correlating and mapping mobile device locations on a mobile device |
9455783, | May 06 2013 | Federal Law Enforcement Development Services, Inc. | Network security and variable pulse wave form with continuous communication |
9461740, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | Building illumination apparatus with integrated communications, security and energy management |
9461748, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light fixture |
9462461, | Jul 12 2005 | Qwest Communications International Inc. | Correlating mobile device locations |
9462462, | Jul 12 2005 | Qwest Communications International Inc. | Providing location-based information to a user of a mobile communication device |
9577760, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | Pulsed light communication key |
9654163, | Apr 01 2009 | Federal Law Enforcement Development Services, Inc. | Visible light transceiver glasses |
9655189, | Mar 13 2013 | Federal Law Enforcement Development Services, Inc. | LED light control and management system |
9660726, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light broad band over power line communication system |
9755743, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light global positioning and routing communication system |
9768868, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | LED light dongle communication system |
9967030, | May 24 2007 | Federal Law Enforcement Development Services, Inc. | Building illumination apparatus with integrated communications, security and energy management |
Patent | Priority | Assignee | Title |
5247380, | Jan 27 1988 | INNSMOUTH LLC | Infrared communications network |
5742238, | Sep 01 1995 | Brooks Automation GmbH | System for communication between a central controller and items in a factory using infrared light |
5745272, | Sep 21 1994 | Hill-Rom Services, Inc | Optical data communication and location apparatus, system and method and transmitters and receivers for use therewith |
6154139, | Apr 21 1998 | VERSUS TECHNOLOGY, INC | Method and system for locating subjects within a tracking environment |
6211790, | May 19 1999 | CENTRAK, INC | Infant and parent matching and security system and method of matching infant and parent |
6225906, | Mar 26 2000 | Patient monitoring and alarm system |
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